Enable lldb-platform exe support for Linux.

This change enables lldb-platform for Linux.  In addition, it does the following:

* fixes Host::GetLLDBPath() to work on Linux/*BSD for ePathTypeSupportExecutableDir-relative paths.

* adds more logging and comments around lldb-platform startup and remote lldb-platform usage.

* refactors lldb-platform remote-* support for Darwin and Linux into PlatformPOSIX.  This, in theory, is the bulk of what is needed for *BSD to make remote connections to lldb-platform as well (although I haven't tested that yet).  FreeBSD can make similar changes to their Platform* as was made here for PlatformLinux to pick up the rest of the bits.

* teaches GDBRemoteCommunication to use lldb-gdbserver for non-Apple hosts.

llvm-svn: 213707

2 files changed, 68 insertions, 42 deletions

diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
index d3ab3b8ec5f..be90eb2b2c9 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
@@ -29,7 +29,11 @@
 // Project includes
 #include "ProcessGDBRemoteLog.h"
 
-#define DEBUGSERVER_BASENAME    "debugserver"
+#if defined(__APPLE__)
+# define DEBUGSERVER_BASENAME    "debugserver"
+#else
+# define DEBUGSERVER_BASENAME    "lldb-gdbserver"
+#endif
 
 using namespace lldb;
 using namespace lldb_private;
@@ -650,6 +654,10 @@ GDBRemoteCommunication::StartDebugserverProcess (const char *hostname,
                                                  lldb_private::ProcessLaunchInfo &launch_info,
                                                  uint16_t &out_port)
 {
+    Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PROCESS));
+    if (log)
+        log->Printf ("GDBRemoteCommunication::%s(hostname=%s, in_port=%" PRIu16 ", out_port=%" PRIu16, __FUNCTION__, hostname ? hostname : "<empty>", in_port, out_port);
+
     out_port = in_port;
     Error error;
     // If we locate debugserver, keep that located version around
@@ -662,7 +670,11 @@ GDBRemoteCommunication::StartDebugserverProcess (const char *hostname,
     // to the debugserver to use and use it if we do.
     const char *env_debugserver_path = getenv("LLDB_DEBUGSERVER_PATH");
     if (env_debugserver_path)
+    {
         debugserver_file_spec.SetFile (env_debugserver_path, false);
+        if (log)
+            log->Printf ("GDBRemoteCommunication::%s() gdb-remote stub exe path set from environment variable: %s", __FUNCTION__, env_debugserver_path);
+    }
     else
         debugserver_file_spec = g_debugserver_file_spec;
     bool debugserver_exists = debugserver_file_spec.Exists();
@@ -676,10 +688,16 @@ GDBRemoteCommunication::StartDebugserverProcess (const char *hostname,
             debugserver_exists = debugserver_file_spec.Exists();
             if (debugserver_exists)
             {
+                if (log)
+                    log->Printf ("GDBRemoteCommunication::%s() found gdb-remote stub exe '%s'", __FUNCTION__, debugserver_file_spec.GetPath ().c_str ());
+
                 g_debugserver_file_spec = debugserver_file_spec;
             }
             else
             {
+                if (log)
+                    log->Printf ("GDBRemoteCommunication::%s() could not find gdb-remote stub exe '%s'", __FUNCTION__, debugserver_file_spec.GetPath ().c_str ());
+
                 g_debugserver_file_spec.Clear();
                 debugserver_file_spec.Clear();
             }
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.cpp
index 8cda558fa5a..b9d59e72ed9 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.cpp
@@ -1824,14 +1824,18 @@ GDBRemoteCommunicationServer::Handle_qLaunchGDBServer (StringExtractorGDBRemote
 #ifdef _WIN32
     return SendErrorResponse(9);
 #else
+    Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM));
+
     // Spawn a local debugserver as a platform so we can then attach or launch
     // a process...
 
     if (m_is_platform)
     {
+        if (log)
+            log->Printf ("GDBRemoteCommunicationServer::%s() called", __FUNCTION__);
+
         // Sleep and wait a bit for debugserver to start to listen...
         ConnectionFileDescriptor file_conn;
-        Error error;
         std::string hostname;
         // TODO: /tmp/ should not be hardcoded. User might want to override /tmp
         // with the TMPDIR environment variable
@@ -1852,53 +1856,57 @@ GDBRemoteCommunicationServer::Handle_qLaunchGDBServer (StringExtractorGDBRemote
         // Spawn a new thread to accept the port that gets bound after
         // binding to port 0 (zero).
 
-        if (error.Success())
-        {
-            // Spawn a debugserver and try to get the port it listens to.
-            ProcessLaunchInfo debugserver_launch_info;
-            if (hostname.empty())
-                hostname = "127.0.0.1";
-            Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM));
-            if (log)
-                log->Printf("Launching debugserver with: %s:%u...\n", hostname.c_str(), port);
+        // Spawn a debugserver and try to get the port it listens to.
+        ProcessLaunchInfo debugserver_launch_info;
+        if (hostname.empty())
+            hostname = "127.0.0.1";
+        if (log)
+            log->Printf("Launching debugserver with: %s:%u...\n", hostname.c_str(), port);
 
-            debugserver_launch_info.SetMonitorProcessCallback(ReapDebugserverProcess, this, false);
-            
-            error = StartDebugserverProcess (hostname.empty() ? NULL : hostname.c_str(),
-                                             port,
-                                             debugserver_launch_info,
-                                             port);
+        debugserver_launch_info.SetMonitorProcessCallback(ReapDebugserverProcess, this, false);
 
-            lldb::pid_t debugserver_pid = debugserver_launch_info.GetProcessID();
+        Error error = StartDebugserverProcess (hostname.empty() ? NULL : hostname.c_str(),
+                                         port,
+                                         debugserver_launch_info,
+                                         port);
 
+        lldb::pid_t debugserver_pid = debugserver_launch_info.GetProcessID();
 
-            if (debugserver_pid != LLDB_INVALID_PROCESS_ID)
-            {
-                Mutex::Locker locker (m_spawned_pids_mutex);
-                m_spawned_pids.insert(debugserver_pid);
-                if (port > 0)
-                    AssociatePortWithProcess(port, debugserver_pid);
-            }
-            else
-            {
-                if (port > 0)
-                    FreePort (port);
-            }
 
-            if (error.Success())
-            {
-                char response[256];
-                const int response_len = ::snprintf (response, sizeof(response), "pid:%" PRIu64 ";port:%u;", debugserver_pid, port + m_port_offset);
-                assert (response_len < (int)sizeof(response));
-                PacketResult packet_result = SendPacketNoLock (response, response_len);
+        if (debugserver_pid != LLDB_INVALID_PROCESS_ID)
+        {
+            Mutex::Locker locker (m_spawned_pids_mutex);
+            m_spawned_pids.insert(debugserver_pid);
+            if (port > 0)
+                AssociatePortWithProcess(port, debugserver_pid);
+        }
+        else
+        {
+            if (port > 0)
+                FreePort (port);
+        }
 
-                if (packet_result != PacketResult::Success)
-                {
-                    if (debugserver_pid != LLDB_INVALID_PROCESS_ID)
-                        ::kill (debugserver_pid, SIGINT);
-                }
-                return packet_result;
+        if (error.Success())
+        {
+            if (log)
+                log->Printf ("GDBRemoteCommunicationServer::%s() debugserver launched successfully as pid %" PRIu64, __FUNCTION__, debugserver_pid);
+
+            char response[256];
+            const int response_len = ::snprintf (response, sizeof(response), "pid:%" PRIu64 ";port:%u;", debugserver_pid, port + m_port_offset);
+            assert (response_len < (int)sizeof(response));
+            PacketResult packet_result = SendPacketNoLock (response, response_len);
+
+            if (packet_result != PacketResult::Success)
+            {
+                if (debugserver_pid != LLDB_INVALID_PROCESS_ID)
+                    ::kill (debugserver_pid, SIGINT);
             }
+            return packet_result;
+        }
+        else
+        {
+            if (log)
+                log->Printf ("GDBRemoteCommunicationServer::%s() debugserver launch failed: %s", __FUNCTION__, error.AsCString ());
         }
     }
     return SendErrorResponse (9);